1. Field of the Invention
The present invention relates to a key unit comprising: a grip case which includes at least a pair of synthetic resin case members joined to each other; and a mechanical key which is supported in the grip case and which includes a key plate capable of being inserted into a cylinder lock and a key head joined to one end of the key plate; the mechanical key being capable of pivoting the mechanical key between a retracted position in which the entire mechanical key is retracted and a projecting position in which the key plate projects.
2. Description of Related Art
Such a key unit is already known from, for example, Japanese Patent Application Laid-open No. 63-110377, in which a key head of a mechanical key is supported in a grip case so that the mechanical key can be shifted between a retracted position in which the entire mechanical key is retracted and a projecting position in which the key plate is made to project.
If a key holder can be connected to the grip case, it is convenient for carrying the key unit. Therefore, there is a demand for a metal holder ring attached to the grip case in order to connect a key holder to the metal holder ring. In the conventional device, an opening for connecting a key holder is generally provided in the grip case. However, the thickness of the grip case has been increasing in recent years due to various additional functions effected by immobilizer communication means built in the key head of the mechanical key, keyless entry communication means built in the grip case and the like, so that a key holder inevitably becomes large in the arrangement where the grip case has an opening for connecting a key holder thereto.
In order to avoid such a situation, it is conceivable that a metal holder ring separate from the grip case is attached to the grip case. In this case, a relatively large load acts on a portion of the holder ring attached to the grip case, and thus an attachment strength capable of withstanding such a load is required for attaching the holder ring to the grip case. Further, it is desirable to facilitate an operation for attaching the holder ring to the grip.